2004 WR450F won't start

My husband has a 2004 WR450F and it won't start. When we try to kick start the bike we can hear it trying to fire, but nothing happens. We took the carb off, and I took it apart to make sure nothing was plugged up or dirty (which I am not an expert on doing). We then put the carb back on and tried to start it. It took a good bit of kick starting but it finally fired up for about 20 seconds, and then died. It wants to fire up, but nothing. We know the battery isn't holding a charge, but our mechanic told us the bike should run even with the battery being junk. Anyone have any tips on what might be wrong?! A little note, my old man put a little of his chainsaw gas in the bike.:rolleyes:

if the chainsaw gas is mix thats yuor porblem. drain the gas and put straight in it change the plug and drain the carb and start it up. the oil in the gas is fowling your plug.if its not premix gas then try a plug, clean the pilot jet again and check your airfilter b sure it is clean from debrie and fire that wr up.

if the chainsaw gas is mix thats yuor porblem. drain the gas and put straight in it change the plug and drain the carb and start it up. the oil in the gas is fowling your plug.if its not premix gas then try a plug, clean the pilot jet again and check your airfilter b sure it is clean from debrie and fire that wr up.

I agree.....

Copesticker,the tank and carb need to be fully cleaned out.. Draining the gas out is not good enough. Take the carb completely off the bike, spray carb cleaner in ALL the passages and blow compressed air to clean them out. Changing the plug is always a good ideal. Also, make sure that you've installed the carb slide plate on correctly, it's a common mistake made by many of us.....

A little note, my old man put a little of his chainsaw gas in the bike.:rolleyes:
:naughty:

When was the last time the bike ran? Has it been sitting along time or had it progressively gotten worse?

My husband has a 2004 WR450F and it won't start. When we try to kick start the bike we can hear it trying to fire, but nothing happens. We took the carb off, and I took it apart to make sure nothing was plugged up or dirty (which I am not an expert on doing). We then put the carb back on and tried to start it. It took a good bit of kick starting but it finally fired up for about 20 seconds, and then died. It wants to fire up, but nothing. We know the battery isn't holding a charge, but our mechanic told us the bike should run even with the battery being junk. Anyone have any tips on what might be wrong?! A little note, my old man put a little of his chainsaw gas in the bike.:rolleyes:

It sounds like it might still have some goo in the carb. The small float area, seems to allow fuel to go sour and leave deposits. Has it set for a winter etc? ANd its worse if it sets out int he cold and rain etc. Try spraying something like brake cleaner in the air cleaner. (brake cleaner makes a great starting fluid) and see if it lights off. It just sounds like you may have a plugged idle circuit, from corrosion from the fuel bowl area. A small wire to poke out the pilot jet etc might help. Good luck, and reply back when you figure it out. I'm curious. (I have the exact same bike)

I pulled the carb off and took it all apart. I sprayed it with carb cleaner and then gently with the air hose. Then put everything back together, and it still won't work. The bike fired up for about 30 seconds then died. The plug is getting spark to it. I'm starting to think it might be something electrical. We put a battery on it that we know works, and when I tried to use the electric start it just clicked then made a quick whining noise. My husband tried to kick start it then, but nothing. I traced all the wire harnesses that I could see, just to make sure they were all connected, and they're all fine.

Did you change the gas?

I put new gas in the bike, and even pulled out the filter to make sure it was ok. This is the events that led up to the problems with the bikes. The bike sat for about 2 weeks before this. My husband said he was out in the woods riding and it was like someone shut the switch off on the bike. He kept trying to get it running again, but it wouldn't do anything. The bike sat for a day after that, and he got it running long enough to ride it less than a mile home from his buddies house. When he pulled in the driveway the bike died, and he couldn't get it started again. That's when we started working on it by draining the gas, pulling the carb off and cleaning it, checking the plug, putting in a different battery (a used one), and changing the air filter. He just got a brand new battery, so we're gonna go look at it some more. He wants to race it tomorrow, but it's looking like he's not going to be able to.

Is gas coming out of the petcock and flowing? I the tank getting vented? I doubt that it's an electical problem..

Well we got the bike fired up, and my husband raced this weekend. I told him to change the spark plug after I had finished pulling off the carb and cleaning it. I assumed he did, but then found out he didn't.:foul: He checked the plug, and it had spark, so he thought he didn't need to change it. Even the mechanic told him that if the old plug had spark it should be fine, but I insisted on him changing it anyway. Once he put in the new plug it started right up. The only thing wrong now is that the electric start doesn't work, but he said we'll worry about that next year or over the winter. He's just happy the bike is running, and I make sure I remind him that he should've listened to me about the spark plug. :)

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